Stranded metal ropes



Jan. 30, G D|ETZ STRANDED METAL ROPES FIG- m @N 0 rD NLM ymv we A T TORNE YS Jan. 30, 1962 G, DIETZ 3,018,606

STRANDED METAL ROPES Filed April 21, 1959 2 Sheets-Sheet 2 VVE/vra@ GERHARD o/Erz my @57M A ORNE YS 3,018,606 STRANDED METAL ROPES Gerhard Dietz, 190 Friedrich-Ebertstrasse, Monchroden, near Coburg, Germany Filed Apr. 21, 1959, Ser. No. 807,838 Claims priority, application Germany Apr. 24, 1958 1l Claims. (Cl. 57-148) This invention relates to stranded metal ropes.

It is known that stranded ropes having parallel-laid outer strands frequently provide Very high rope performances, especially when the inner and outer strands are so arranged as not to overlap. Experience has also shown that helical stranded ropes themselves, when they are twisted with a parallel lay, have great advantages for many purposes of use.

A. serious problem however, is the fact that ropes with parallel lay are subject to unfavourable stresses in the region of their inner strands, which stresses, especially under tensile load, frequently lead to a premature destruction of the internal rope structure, while the rope is still intact externally. The reason for this is to be found in the fact that the supporting metal cross-section of the inner strands is greatly reduced relatively to the outer strands, while at the same time the loading of these inner strands is very high. The latter is again to be attributed to the fact that with parallel-laid ropes, the amplitude of the helices or spirals described by the inner strands in the rope is smaller than those of the outer strands, so that the inner strands in the rope are shorter than the outer strands, disregarding the core or heart strand, which extends rectilinearly.

The invention has for its object a new rope construction by which the disadvantages set forth can be obviated. Starting from a rope twisted with a parallel lay, the invention provides for the rope having parallel-laid strands in the region of the rope cross-section subject to high stressing, ie., advantageously in the zone of the series of inner strands. By this means, a rope is in fact provided which has an adequate metal cross-section in the Zone where stressing is particularly high, and consequently permits far better performance than was formerly the case.

In the manufacture of the new helical stranded rope, the procedure is advantageously that not only the inner strands, but also the outer strands, are manufactured with a parallel lay. Furthermore, it is an essential feature of the invention that the heart strand or core of the new rope is either greatly reduced in cross-section or is even completely omitted.

By the use of parallel-laid inner strands in a helical stranded rope, which externally is also of parallel-laid construction, somewhat more pronounced cavities are produced between the inner strands and the outer strands in Contact therewith, due to the increase in the crosssections of said inner strands, and according to the invention thin filler strands are expediently introduced into these cavities.

The high performance of a rope according to the invention can be further improved by making use of known features which permit the elimination of overlap of wires on the contact lines between outer and inner strands. In particular, this is possible by for example using unidirectional lay in the outer series of strands and Langs or cross lay in the inner series of strands, and in addition, by choosing certain pitch heights, it is possible to produce an absolutely parallel direction of the wires of contiguous strand.

The invention will be further described with reference to the accompanying drawings, in which FIGURES l to 3 each show a diagrammatic cross-section through a helical stranded rope.

ite rates Patent ICC Referring first to FIGURE 1, which shows a parallellaid rope of known construction, it will be seen that an inner series of strands 7 is arranged between the parallel-laid strands 5 of the outer strand series and the comparatively large heart strand or core 6, the said inner strands consisting in the normal manner of l X 6 wires. It is inherent in the structure of such a rope that the inner strands have a comparatively small metal crosssection, although it is just in this zone that there is a high stressing of the rope cross-section.

FIGURE 2 relates to a first embodiment of a helical stranded rope according to the invention made with parallel lay. In this case, a series of inner strands 10 is interposed lbetween the outer series 8 of parallel-laid strands and quite a thin heart strand or core 9, the individual strands 10 also having a parallel lay, as can be seen from the heart wire 11, the inner wires 12 and the outer wires 13.

In this Way, the metal cross-section of the highly stressed inner strands is increased appreciably in relation to the outer strands and for the reasons already explained, this leads to a considerable improvement in the performance 0f the rope.

In order that the total cross-section of the rope may be filled in a favourable manner, a filler strand 1S is incorporated between each two outer strands 14 and 15 and the adjoining inner strands 16 and 17.

As regards the embodiment of the invention shown in FIGURE 3, this relates to a rope in `which the inner strands 19 again have a parallel lay, are supplemented by filler strands 20, and are arranged immediately adjacent one another so that a heart strand or core can be omitted, this being advantageous not only asregards the working capacity of the rope, but also producing advantages as regards manufacture.

What I claim is:

1. A helical stranded Wire rope comprising an inner series of at least three parallel helically wound strands of wires, a contiguous outer series of a greater number of parallel helically wound strands of wires, the strands of the outer series lying parallel to the strands of the innery series, each strand of the'inner vseries comprising an,

inner and outer series of parallel wires arranged in,

parallel lay, the strands of the inner series defining between them a center zone of smaller cross sectional area than any of said strands.

2. A helical stranded wire rope comprising an inner series of at least three parallel helically wound strands of wires, a contiguous outer series of a greater number of parallel helically wound strands of wires, the strands of the outer series lying parallel to the strands of the inner series, each strand of the inner series comprising an inner and outer series of parallel wires arranged in parallel lay, the strands of the inner series defining between them an unfilled center zone of smaller cross sectional area than any of said strands.

3. A helical stranded wire rope comprising an inner series of at least three parallel helically wound strands of wires, a contiguous outer series of a greater number of parallel helically wound strands of wires, the strands of the outer series lying parallel to the strands of the inner series, each strand of the inner series comprising an inner and outer series of parallel wires arranged in parallel lay, the strands of the inner series defining between them a center zone of smaller cross sectional area than any of said strands, and a thin heart strand of helically wound wires filling said center zone.

4. A helical stranded wire rope comprising an inner series of at least three parallel helically wound strands of wires, a contiguous outer series of a greater number of parallel helically wound strands of wires, the strands of the outer series lying parallel to the strands of the inner series, each strand of the inner series comprising an inner and outer series of parallel wires arranged in parallel lay, the strands of the inner series defining between them a center zone of smaller cross sectional area than any of said strands, there being an interstice between each two contiguous strands of the inner series and an adjacent two contiguous strands of said outer series, and a relatively thin strand of helically wound wires filling each of said interstices.

5. A helical stranded wire rope comprising an inner series of at least three parallel helically wound strands of wires, a contiguous outer series of a greater number of parallel helically wound strands of wires, the strands of the outer series lying parallel to the strands of the inner Series, each strand of the inner series comprising an inner and outer series of parallel wires arranged in parallel lay, the strands of the inner series defining between them a center zone of smaller cross sectional area than any of said strands, the contacting wires of contiguous inner and outer strands of the said series of strands being parallel along their lines of contact.

6. A helical stranded wire rope comprising an inner series of at least three parallel helically wound strands of wires, a contiguous outer series of a greater number of parallel helically wound strands of wires, the strands of the outer series lying parallel to the strands of the inner series, each strand of the inner series comprising an inner and outer series of parallel wires arranged in parallel lay, the strands of the inner series defining between them a center zone of smaller cross sectional area than any of said strands, there being an interstice between each two contiguous strands of the inner series and an adjacent two contiguous strands of said outer series, and a relatively thin strand of helically wound wires filling each of said interstices, the contacting wires of contiguous inner and outer strands of the said series of strands being parallel along their lines of contact.

7. A helical stranded wire rope, comprising an inner series of at least three parallel helically wound strands of wires and a contiguous outer series of a greater number of parallel helically wound strands of Wires, the strands of the outer series lying parallel to the strands of the inner series, each strand of each of said series com.- prising an inner and outer series of parallel helically Wound wires arranged in parallel lay, the strands of the inner series defining between them a center zonc of smaller cross sectional area than any of said strands.

8. A helical stranded wire rope comprising an inner series of three parallel helically wound strands of wires, these strands defining between them an unfilled center zone of much smaller cross sectional area than any of them, a contiguous outer series of six parallel helically wound strands of wires, the strands of the outer series lying parallel to the strands of the inner series, each strand of each of said series comprising an inner and outer series of parallel helically wound lwires arranged in parallel lay, there being an interstice between each two contiguous strands of the inner series and an adjacent two contiguous strands of the outer series, and a relatively thin strand of helically wound wires filling each of said interstices.

9. A wire rope as claimed in claim 8, the contacting wires of contiguous inner and outer strands of the said series of strands being parallel along their lines of contact.

10. A helical stranded wire rope comprising an inner series of four parallel helically wound strands of wires, these strands defining between them a center zone of smaller cross sectional area than any of them, a thin heart strand of helically wound wires filling said zone, an outer series of eight parallel helically wound strands of wires, the strands of the outer series lying contiguous and parallel to the strands of the inner series, each strand of each of said series comprising an inner and outer series of parallel helically wound wires arranged in parallel lay, there being an interstice between each two contiguous strands of the inner series and an adjacent two contiguous strands of the outer series, and a thin strand of helically wound wires lling each of said interstices.

11. A wire rope as claimed in claim 10, the contiguous inner and outer strands of the said series of strands being parallel along their lines of contact.

References Cited in the file of this patent UNITED STATES PATENTS 416,189 Stone Dec. 3, 1889 952,161 Whyte Mar. 15, 1910 1,481,801 Harrison Jan. 29, 1924 1,757,156 Wirkkala May 6, 1930 2,562,340 Stanton July 31, 1951 2,567,300 Riddle Sept. 11, 1951 

